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The International Classification of Sleep
Disorders Classification Outline ________________
______ 1. Dyssomnias A. Intrinsic Sleep
Disorders B. Extrinsic Sleep Disorders C.
Circadian Rythm Sleep Disorders 2.
Parasomnias A. Arousal Disorders B. Sleep-Wake
Transition Disorders C. Parasomnias usually
asscociated with REM Sleep D. Other Parasomnias
3. Medical/Psychiatric Sleep Disorders A.
Associated with Mental Disorders B. Associated
with Neurological Disorders C. Associated with
Other Medical Disorders 4. Proposed Sleep
disorders List ... Reference ICSD -
International classification of sleep disorders
Diagnostic and coding manual. Diagnostic
Classification Steering Committee, Thorpy MJ,
Chairman. Rochester, Minnesota American Sleep
Disorders Association, 1990.
A. Intrinsic Sleep Disorders 1.
Psychophysiological Insomnia 2. Sleep State
Misperception 3. Idiopathic Insomnia 4.
Narcolepsy 5. Recurrent Hypersomnia 6. Idiopathic
Hypersomnia 7. Posttraumatic Hypersomnia 8.
Obstructive Sleep Apnea Syndrome 9. Central Sleep
Apnea Syndrome 10. Central Alveolar
Hypoventilation Syndrome 11. Periodic Limb
Movement Disorder 12. Restles Legs Syndrome 13.
Intrinsic Sleep Disorder NOS
Psychopysiological Insomnia ICSD304.42-0 ICD-10
F51.0 (Nonorganic Insomnia) DSM-IV307.42 (Primary
Insomnia) Psychopysiological Insomnia is a
disorder of somatized tension and learned
sleep-preventing associations that result in a
complaint of insomnia and associated decreased
functioning during wakefulness. Prevalence In
sleep disorders centers, about 15 of all
insomniacs receive a diagnosis of
psychophysiological insomnia. The true incidence
rate in the general population is unknown.
Learned sleep preventing associations, while
paramount in psychophysiological insomnia, also
tend to play an important role in most other
forms of chronic insomnia. Keywordspsychopysiol
ogical insomnia, learned insomnia, conditioned
insomnia, functionally anonymous insomnia,
psychophysiological arousal, chronic somatized
tension, internal arousal without
Sleep State Misperception ICSD307.49-1 ICD-10F
51.8 (Other Nonorganic Sleep Disorder) DSM-IV307.
42 (Primary Insomnia) Sleep State Misperception
is a disorder in which a complaint of insomnia
or excessive sleepiness occurs without objective
evidence of sleep disturbance. Prevalence The
prevalence of the sleep state misperception is
not known. However, it appears to comprise less
than 5 of all patients presenting with
insomnia. KeywordsPseudoinsomnia, subjective
DIMS complaint without objective findings,
insomnia without objective findings, sleep
hypochondriasis, subjective complaint.
Idiopathic Insomnia ICSD780.52-7 ICD-10G47.0 (D
isorders of Initiating and Maintaining Sleep
(Insomnias)) DSM-IV307.42 (Primary
Insomnia) Idiopathic Insomnia is a lifelong
inability to obtain adequate sleep that is
presumably due to an abnormality of the
neurological control of the sleep-wake system.
Prevalence Prevalence figures are unknown. In
its pure form the disorder is rare. Most sleep
disturbances in childhood are associated with
behavioral-psychological issues, not with
idiopatic insomnia. KeywordsChildhood-onset
insomnia, lifelong insomnia, insomnia associated
with problems within the sleep-wake system,
excessive arousal, inadequately developed sleep
Narcolepsy ICSD347 ICD-10G47.4 (Narcolepsy and
Cataplexy) DSM-IV347 (Narcolepsy) Narcolepsy
is a disorder of unknown etiology, which is
characterized by excessive sleepiness that
typically is associated with cataplexy and other
REM sleep phenomena such as sleep paralysis and
hypnagogic hallucinations. Prevalence
Narcolepsy is estimated to occur in 0.03 - 0.16
of the general population. Israeli studies
indicate a much lower frequency in Israeli Jews,
which may be related to the low percentage of
human leucocyte antigen DR2 (HLA-DR2) in the
Israeli Jewisch population (3) as compared to
the North American population (10-35)
Keywordsexcessive sleepiness, abnormal REM
sleep, cataplexy, sleep paralysis, hypnagogic
hallucinations, nocturnal sleep disruption,
positive HLA DR2 or Dw2, genetic component
Recurrent Hypersomnia ICSD780.54-2 ICD-10G47.8
(Other Sleep Disorder) DSM-IV307.44 (Primary
Hypersomnia) Recurrent Hypersomnia is a
disorder characterized by recurrent episodes of
hypersomnia that typically occur weeks or months
apart. Prevalence The prevalence rate is
unknown. Keywordsperiodic hypersomnia,
Kleine-Levin syndrome, binge eating,
hypersexuality (excludes menstrual-associated
sleep disorder)
Idiopathic Hypersomnia ICSD780.54-7 ICD-10G47.1
(Disorders of Excessive Somnolence
(Hypersomnias)) DSM-IV307.44 (Primary
Hypersomnia) Recurrent Hypersomnia is a
disorder characterized by recurrent episodes of
hypersomnia that typically occur weeks or months
apart. Prevalence The prevalence rate is
unknown. Keywordsperiodic hypersomnia,
Kleine-Levin syndrome, binge eating,
hypersexuality (excludes menstrual-associated
sleep disorder)
Posttraumatic Hypersomnia ICSD780.54-8 ICD-10G4
7.1 (Disorders of Excessive Somnolence
(Hypersomnias)) DSM-IV780.54 (Sleep Disorder Due
to a General Medical Condition Hypersomnia
Type) Posttraumatic Hypersomnia is exessive
sleepiness that occurs as a result of a traumatic
event involving the central nervous system.
Prevalencenot known Keywords Posttraumatic
hypersomnia, secondary hypersomnolence
Obstructive Sleep Apnea Syndrome ICSD780.53-0 IC
D-10G47.3 (Sleep Apnea) E66.2 (Pickwickian
Syndrome) DSM-IV780.59 (Breathing-Related Sleep
Disorder) Obstructive sleep apnea syndrome is
characterized by repetitive episodes of upper
airway obstruction that occur during sleep,
usually associated with a reduction in blood
oxygen saturation. Prevalence Obstructive
sleep apnea syndrome is most common in middle
aged, overweight males. Although an accurate
figure is not available, a prevalence of 1-2 of
the population is suspected. Reference
Data PatientNotesMR006Obstructive sleep apnea
syndrome combined with PLM Keywordssleep apnea,
obstructive apnea, upper airway apnea, mixed
apnea, hypersomnia sleep apnea syndrome, obesity
hypoventilation syndrome, adenoidal hypertrophy,
cor pulmonale syndrome, pickwickian syndrome.
Central Sleep Apnea Syndrome ICSD780.51-0 ICD-1
0G47.3 (Sleep Apnea) R06.3 (Periodic
Breathing) DSM-IV780.59 (Breathing-Related Sleep
Disorder) Central sleep apnea syndrome is
characterized by cessation or decrease of
ventilatory effort during sleep usually with
associated oxygen desaturation. Prevalence
Central sleep apnea can be asymptomatic
therefore, its exact prevalence is unknown. It is
considered pathological only when the events are
sufficiently frequent to disturb sleep or result
in hypoxemia or cardiac changes.
Keywordscentral apnea, nonobstructive sleep
apnea, Cheyne-Stokes respiration.
Central Alveolar Hypoventilation
Syndrome ICSD780.51-1 ICD-10G47.3 (Sleep
Apnea) DSM-IV780.59 (Breathing-Related Sleep
Disorder) Central Alveolar Hypoventilation
Syndromeis characterized by ventilatory
impairment, resulting in arterial oxygen
desaturation that is worsened by sleep, which
occurs in patients with normal mechanical
properties of the lung. definition Prevalence
Not known, but the idiopatic form is quite
rare. KeywordsCentral alveolar
hypoventilation, primary alveolar
hypoventilation, idiopatic alveolar
hypoventilation, non-apneic alveolar
Periodic Limb Movement Disorder
ICSD780.52-4 ICD-10G25.8 (Other Specified
Extrapyramidal and Movement Disorders) DSM-IV307.
47 (Dyssomnia NOS ) Periodic Limb Movement
Disorder is characterized by periodic episodes
of repetitive and highly stereotype limb
movements that occur during sleep. Prevalence
The prevalence is not known. It appears to be
rare in children and progresses with advancing
age to become a common finding in up to 34 of
patients over the age of 60 years. It has been
reported to occur in 1-15 of patiets with
insomnia. Reference Data PatientNotesMR006Ob
structive sleep apnea syndrome combined with
PLM Keywordsperiodic leg movements (PLMs),
nocturnal myoclonus, periodic movements in sleep
(PMS), leg jerks.
Restless Legs Syndrome ICSD780.52-5 ICD-10G25.
8 (Other Specified Extrapyramidal and Movement
Disorders) DSM-IV307.47 (Dyssomnia NOS
) Restless Legs Syndrome is a disorder
characterized by disagreeable leg sensations,
usually prior to sleep onset, that cause an
almost irresistable urge to move the legs.
Prevalence Definitive data are not available.
Symptoms of restles legs syndrome have been
identified in 5-15 of normal subjects, 11 of
pregnant women, 14-20 of uremic patients, and up
to 30 of patients with rheumatoid arthritis.
Keywordsrestless legs syndrome (RLS),
disagreeable sensations in legs.
B. Extrinsic Sleep Disorders 1. Inadequate Sleep
Hygiene 2. Environmental Sleep Disorder 3.
Altitude Insomnia 4. Adjustment Sleep Disorder 5.
Insufficient Sleep Syndrome 6. Limit-Setting
Sleep Disorder 7. Sleep-Onset Association
Disorder 8. Food Allergy Insomnia 9. Nocturnal
Eating (Drinking) Syndrome 10.
Hypnotic-Dependent Sleep Disorder 11.
Stimulant-Dependent Sleep Disorder 12.
Alcohol-Dependent Sleep Disorder 13.
Toxin-Induced Sleep Disorder 14. Extrinsic Sleep
Disorder NOS
C. Circadian Rhythm Sleep Disorders 1. Time Zone
Change (Jet Lag) Syndrome 2. Shift Work Sleep
Disorder 3. Irregular Sleep-Wake Pattern 4.
Delayed Sleep Phase Syndrome 5. Advanced Sleep
Phase Syndrome 6. Non-24-Hour Sleep-Wake
Disorder 7. Circadian Rhythm Sleep Disorder NOS
Time Zone Change (Jet Lag) Syndrome ICSD307.45-0
ICD-10G47.2 (Disorders of The Sleep-Wake
Schedule) DSM-IV307.45 (Circadian Rhythm Sleep
Disorder) Time zone change (jet lag) syndrome
consists of varying degrees of difficulties in
initiating or maintaining sleep, excessive
sleepiness, decrements in subjective daytime
alertness and performance, and somatic symptoms
(largely related to gastrointestinal function)
following rapid travel across multiple time
zones. Prevalence Not known. KeywordsJet
lag, transmeridian flight desynchronosis, air
travel, transmeridian dyschronism
Shift Work Sleep Disorder ICSD307.45-1 ICD-10G
47.2 (Disorders of The Sleep-Wake
Schedule) DSM-IV307.45 (Circadian Rhythm Sleep
Disorder) Shift work sleep disorder consists of
symptoms of insomnia or excessive sleepiness that
occur as transient phenomena in relation to work
schedules. Prevalence The prevalence depends
on the prevalence of shift work in the
population. It appears, that a majority of
individual experience sleep difficulties after a
night shift. Depending on which country is
considered, between 5 and 8 of the population is
exposed to night work on a regular or irregular
basis. Thus, a prevalence of shift work sleep
disturbance of 2-5 may be a reasonable estimate.
These figures do not, however, involve
individuals with early morning work, which may be
another group of risk.. KeywordsNight shift,
irregular work hours, transient insomnia,
transient excessive sleepiness, work shift change
in conventional sleep-wake schedule, acute phase
shift of sleep, frequently changing
Irregular Sleep-Wake Pattern ICSD307.45-3 ICD-10
G47.2 (Disorders of The Sleep-Wake
Schedule) DSM-IV307.45 (Circadian Rhythm Sleep
Disorder) Irregular sleep-wake pattern consists
of temporally disorganized and variable episodes
of sleep and waking behavior. Prevalence
Apparently rare in the general population. The
prevalence in patients with diffuse brain
dysfunction is unknown, but the syndrome is
probably not uncommon in severely impaired,
institutionalized patients. KeywordsNo
circadian rhythm, disregard of Zeitgebers,
grossly disturbed sleep-wake rhythm, low
amplitude circadian rhythms.
Delayed Sleep Phase Syndrome ICSD780.55-0 ICD-1
0G47.2 (Disorders of The Sleep-Wake
Schedule) DSM-IV307.45 (Circadian Rhythm Sleep
Disorder) Delayed sleep phase syndrome is a
disorder, in which the major sleep episode is
delayed in relation to the desired clock time
that results in symptoms of sleep-onset insomnia
or difficulty in awakening at the desired time.
Prevalence Unknown probably uncommon,
representing a small portion (5-10) of patients
presenting to sleep disorders centerswith the
complaint of insomnia. The general population
prevalence is unknown. One survey study on
adolescents found evidence suggesting a 7
prevalence in this age-group. There may be
individuals who adapt to the pattern by taking
evening or night jobs. KeywordsPhase lag,
phase delay, sleep-onset insomnia, morning
sleepiness, stable asynchrony relative to typical
environmental pattern.
Advanced Sleep Phase Syndrome ICSD780.55-1 ICD-
10G47.2 (Disorders of The Sleep-Wake
Schedule) DSM-IV307.45 (Circadian Rhythm Sleep
Disorder) Advanced sleep phase syndrome is a
disorder in which the major sleep episode is
advanced in relation to the desired clocktime,
that results in symptoms of compelling evening
sleepiness, an early sleep onset, and an
awakening that is earlier than desired.
Prevalence Apparently rare. KeywordsPhase
advance, stable asynchrony relative to typical
environmental pattern, evening somnolence and
early morning wakefulness, extreme larkishness.
Non-24-Hour Sleep-Wake Disorder
ICSD780.55-2 ICD-10G47.2 (Disorders of The
Sleep-Wake Schedule) DSM-IV307.45 (Circadian
Rhythm Sleep Disorder) Non-24-hour sleep-wake
disorder consists of a chronic steady pattern
comprised of 1-2 hour daily delays in sleep onset
and wake times in an individual living in
society. Prevalence Apparently rare in the
general population. Althought the prevalence in
the blind is unknown, one survey of blind
individuals revealed a high incidence of
sleep-wake complaints, with 40 of the
respondents having recognized that their symptoms
ocurred in a cyclic pattern. KeywordsFree-runn
ing pattern, incremental asynchrony relative to
typical environmental pattern, periodic insomnia,
periodic excessive sleepiness, blindness,
hypernycthemeral syndrome.
  • 2. Parasomnias
  • Arousal Disorders
  • 1. Confusional Arousals
  • 2. Sleepwalking
  • 3. Sleep Terrors

Confusional Arousals consists of confusion
during and following arousals from sleep, most
typically from deep sleep in the first part of
the night. Prevalence Repeated confusional
arousals are almost universal in young children
before the age of about 5 years they become much
less common in older childhood. Confusional
arousals are fairly rare in adulthood, during
which their precise prevalence is undocumented.
KeywordsSleep drunkenness, excessive sleep
inertia, Schlaftrunkenheit, livresse du sommeil.

Sleepwalking ICSD307.46-0 ICD-10F51.3 (Sleepw
alking (Somnambulism)) DSM-IV307.46 (Sleep
Terror Disorder) Sleepwalking consists of a
series of complex behavours that are initiated
during slow wave sleep and result in walking
during sleep. Prevalence The incidence of
sleepwalking is between 1 and 15 in the general
population. The disorder is more common in
children than in adolescents and adults.
KeywordsSomnambulism, semipurposeful
automatisms, amnesia, nonepileptic.
Sleep Terrors ICSD307.46-1 ICD-10F51.4 (Sleep
Terrors (Night Terrors)) DSM-IV307.46 (Sleep
Terror Disorder) Sleep terrors are
characterized by a sudden arousal from slow wave
sleep with a piercing scream or cry, accompanied
by autonomic and behavioral manifestations of
intense fear. Prevalence The prevalence is
approximately 3 of children and less than 1
of adults. KeywordsPavor nocturnus, incubus,
severe autonomic discharge, night terror.
B. Sleep-Wake Transition Disorders 1. Rhythmic
Movement Disorder 2. Sleep Starts 3. Sleep
Talking 4. Nocturnal Leg Cramps
Rhythmic Movement Disorder ICSD307.3 ICD-10F98.
4 (stereotyped movement disorder) DSM-IV307.3 (rh
ythmic movement disorder) Rhythmic Movement
Disordercomprises a group of stereotyped,
repetitive movements involving large muscles,
usually of the head and neck, which typically
occur immediately prior to sleep and are
sustained into light sleep. Prevalence Some
form of rhythmic activity is found in two-thirds
of all infants at 9 month of age. By 18 month,
the prevalence has declined to less than half,
and by 4 years, it is only 8. Bodyrocking is
more common in the first year, but headbanging
and headrolling are more frequent in older
children. KeywordsJactatio capitis nocturna,
headbanging, headrolling, bodyrocking,
bodyrolling, rhythmie du sommeil.
Sleep Starts ICSD307.47-2 ICD-10G47.8 (other
sleep disorder) DSM-IV307.47 (parasomnia
NOS) Sleep Starts are sudden brief contractions
of the legs, sometimes also involving the arms
and head, which occur at sleep onset.
Prevalence Sleep starts are an essentially
universal component of the sleep-onset process,
although often they are not recalled. A
prevalence of 60-70 has been reported. Sleep
starts are rare in extreme forms, and can cause
sleep onset difficulties. KeywordsHypnagogic
jerks, predormital myoclonus, hypnic jerks.
Sleep Talking ICSD307.47-3 ICD-10F51.8 (other
non-organic sleep disorder) DSM-IV307.47 (parasom
nia NOS) Sleep Talkingis the utterance of
speech or sounds during sleep without
simultaneous subjective detailed awareness of the
event. Prevalence Not known, but apparently
very common. Sleep talking that is of major
annoyance to others is rare. KeywordsSomniloqu
y, utterances, moans, verbalisation.
Nocturnal Leg Cramps ICSD729.82 ICD-10R25.2
(cramp and spasm)DSM-IV307.47 (parasomnia
NOS) Nocturnal Leg Crampsare painful sensations
of muscular tightness or tension, usually in the
calf, but occasionally in the foot that occur
during the sleep episode. Prevalence Definite
data are not available. Symptoms of nocturnal leg
cramps have been identified in up to 16 of
healthy individuals, particulary following
vigorous exercise, with an increasing incidence
among the elderly. Keywordsleg cramps, muscle
tightness of the leg, muscle hardness, nocturnal
pain, Charley-horse.
  • C. Parasomnias Usually Associated with REM Sleep
  • Nightmares
  • 2. Sleep Paralysis
  • 3. Impaired Sleep-Related Penile Erections
  • 4. Sleep-Related Painful Erections
  • 5. REM Sleep Related Sinus Arrest
  • 6. REM Sleep Behavior Disorder

Nightmares ICSD307.47-0 ICD-10F51.5 (Nightmar
es) DSM-IV307.47 (Nightmare Disorder) Nightmares
are frightening dreams that usually awaken the
sleeper from REM sleep. Prevalence There is no
definite agreement between studies. Apparently,
10-50 of children at the age of 3-5 have enough
nightmares to disturb the parents. A larger
percentage, probably 75 , can remember at least
one or a few nightmares in the course of their
childhood.Approximately 50 of adults admit to
having at least an occasional nightmare. The
condition of frequent nightmares (one or more a
week) occurs in perhaps 1 of the adult
population. KeywordsNightmare, dream anxiety
attack, terrifying dream, REM-nightmare.
Sleep Paralysis ICSD780.56-2 ICD-10G47.4 (Narco
lepsy and Cataplexy) DSM-IV307.47 (Parasomnia
NOS) Sleep Paralysis consists of a period of
inability to perform voluntary movements either
at sleep onset (hypnagogic or predormital form)
or upon awakening either during the night or in
the morning (hypnopompic ot postdormital form).
Prevalence Isolated sleep paralysis occurs at
least once in a lifetime in 40-50 of normal
subjects. As a chronic complaint, however, it is
much less common. Surveys of normal subjects have
indicated sleep paralysis in 3-6 of respondents,
many of whom had rare episodes. Familial sleep
paralysis in individuals lacking sleep atacks or
cataplexy is exceptionally rare, with only a few
families described in the literature. Seventeen
to 40 of narcoleptics have been reportet to have
sleep paralysis. KeywordsIsolated sleep
paralysis, familial sleep paralysis, hypnagogic
and hypnopompic paralysis, predormital and
postdormital paralysis
Impaired Sleep-Related Penile Erections ICSD780.
56-3 ICD-10N48.4 (Other Disorders of
Penis) DSM-IV607.84 (Male Erectile Disorder Due
to a General Medical Condition) Impaired
sleep-related penile erectionsrefers to the
inability to sustain a penile erection during
sleep that would be sufficiently large or rigid
enough to engage in sexual intercourse.
Prevalence Is estimated that more than 10 of
adult males in the United States have chronic
erectile dysfunction. The majority (60-70) are
thought to have organic impotence.
Differentiation of organic and nonorganic
impotence requires sophisticated testing and
clinical skill. Moreover, the samples of patients
at particular clinics may be biased because of
selection forcescreated by the institutions
reputations. For these two reasons, it may be
difficult to obtain precise prevalence data.
KeywordsImpaired nocturnal penile tumescence
(NPT), impotence, organic impotence, erectile
dysfunction, erectile failure, sexual dysfunction
Sleep-Related Painful Erections ICSD780.56-4 ICD
-10G47.0N48.8 (Disorders of Initiating and
Maintaining Sleep (Insomnias) Other Disorders
of Penis) DSM-IV607.89 (Other Male Sexual
Dysfunction Due to a General Medical
Condition) Sleep-related painful erectionsare
characterized by penile pain that occurs during
erections, typically during REM sleep.
Prevalence This disorder is rare occuring in
less than 1 of patients presenting with sexual
and erectile problems. KeywordsPainful
REM Sleep Related Sinus Arrest ICSD780.56-8 ICD
-10I46.8 (I46 Cardiac Arrest) DSM-IV? REM
sleep related sinus arrestis a cardiac rhythm
disorder that is characterized by sinus arest
during REM sleep in otherwise healthy
individuals. Prevalence No information is
available on the prevalence of this disorder.
Because the disorder in most cases is
asymptomatic and presumably undiagnosed, this
information will be difficult to obtain.
KeywordsNocturnal asystole, sinus arrest.
REM Sleep Behavior Disorder ICSD780.59-0 ICD-10
G47.8 (Other Sleep Disorder ) DSM-IV307.47 (Para
somnia NOS) REM Sleep Behavior Disorderis
characterized by intermittent loss of REM sleep
electromyographic (EMG) atonia and by the
appearance of elaborate motor activity associated
with dream mentation. Prevalence REM sleep
behavior disorder is apparently rare However,
many cases are probably masquerading as other
parasomnias. KeywordsREM sleep behavior
disorder (RBD), oneirism, acting out of dreams,
REM motor parasomnia.
D. Other Parasomnias 1. Sleep Bruxism 2. Sleep
Enuresis 3. Sleep-Related Abnormal Swallowing
Syndrome 4. Nocturnal Paroxysmal Dystonia 5.
Sudden Unexplained Nocturnal Death Syndrome 6.
Primary Snoring 7. Infant Sleep Apnea 8.
Congenital Central Hypoventilation Syndrome 9.
Sudden Infant Death Syndrome 10. Benign Neonatal
Sleep Myoclonus 11. Other Parasomnia NOS
3. Medical/Psychiatric Sleep Disorders A.
Associated with Mental Disorders B. Associated
with Neurological Disorders C. Associated with
Other Medical Disorders